1. Field of the Invention
This invention relates to a process for the production of optically active 5-methyl-2-(1-methylbutyl)5-propyl-1,3-dioxane, to the product obtainable by this process and to its use as a perfume.
2. Statement of Related Art
Judging by demand, many natural perfumes are available in totally inadequate quantities. For example 5000 kg of rose blossoms are required to produce 1 kg of rose oil. The consequences are extremely limited annual world production and a high price. Accordingly, it is clear that there is a constant need in the perfume industry for new perfumes with interesting fragrance notes in order to extend the range of naturally available perfumes, to make the necessary adaptations to changing fashion trends and to be able to meet the steady increasing demand for odor enhancers for products of everyday use, such as cosmetics and cleaners.
Accordingly, it is dear that there is a constant need in the perfume industry for new perfumes with interesting fragrance notes in order to extend the range of naturally available perfumes, to make the necessary adaptations to changing fashion trends and to be able to meet the steadily increasing demand for odor enhancers for products of everyday use, such as cosmetics and cleaners.
In addition, there is generally a constant need for synthetic perfumes which can be favorably produced in a consistent quality and which have desirable olfactory properties, i.e. pleasant, near-natural and qualitatively new odor profiles of adequate intensity, and which are capable of advantageously influencing the fragrance of cosmetic and consumer products. In other words, there is a constant need for compounds which have characteristic new odor profiles coupled with high staying power, intensity of odor and emanative power. 5-Methyl-2-(1-methylbutyl)-5-propyl-1,3dioxane 22 (trade name Troenan.RTM.) ##STR1##
is a known synthetic perfume obtainable from 2-methyl pentanal 23 (cf. following scheme). The educt 23 is reacted with 2 equivalents of formaldehyde in a crossed Canizzaro reaction to form 2-methyl-2-propylpropane-1,3-diol 24. The diol 24 may then be acetalized with 2-methylpentanal 23 to form Troenan.RTM. 22. ##STR2##
By virtue of its privet blossom note, Troenan.RTM. is valued for flowery and aromatic formulations, more particularly lily-of-the-valley compositions. It has the advantage over other lily-of-the-valley components that it is stable to alkalis.
Troenan.RTM. 22 contains two cis/trans isomers which in turn consist of two enantiomers: ##STR3##